<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>嵌套列表</title>
</head>
<body>

<h4>一个嵌套列表：</h4>
<ul>
  <li>咖啡</li>
  <li>茶
    <ul>
      <li>红茶</li>
      <li>绿茶</li>
    </ul>
  </li>
  <li>牛奶</li>
</ul>

</body>
</html>